Hydraulically balanced pressure roll for glue machines



876,734 HYDRAULICALLY BALANCED PRESSURE ROLL FOR GLUE MACHINES C. D.NITCHIE March 10, 1959 Filed April 11, 1956 INVENTORL CHARLES D. NITCHIEATTYS.

United States atent HYDRAULI'CALLY BALANCED PRESSURE ROLL FOR GLUEMACHINES Charles D. Nitchie, Haddonfield, N. J., assignor to Samuel M.Langston 'Co., Camden, N. J., a corporation of New Jersey ApplicationApril 11, 1956, Serial No. 577,516 9 Claims. (Cl. 118-249) In theproduction of double faced corrugated board, it is necessary afterapplication of the facing liner on one face of the board .to apply glueto the tips of the flutes at the other face prior to application of thesecond facing liner. conventionally, this is accomplished by means of aglue machine comprising a glue applicator roll, a doctor or meteringroll, and a rider or pressure roll. The function of the rider roll is topress the single faced corrugated web down into'the film of glue on theappli- Lcator roll to insure transfer of adhesive.

Heretofore, a heavy rider roll has been used and this roll has beenpositioned dimensionally from the glue roll a fixed distance so thatpressure of each flute into the glue film is assured. Adjustment of theroll has been by manual feel, the practice being to set the roll bymeans of suitable adjustment devices so that the roll, which is drivenby contact with the paper, exhibits a certain torque by feel whengrasped with both hands.

conventionally also, the roll is pivotally mounted on arms so that itmay swing up. To prevent bouncing, however, its weight has had to besuch that in the absence of positive stops it would crush thecorrugations. Obviously, with a fixed adjustment of this character, ifthe thickness of the single faced board changes, and if the operator isnot alert, the flutes are either crushed or receive insuflicientadhesive.

A principal object of this invention is to provide means whereby aconstant pressure may be exerted on the web by the rider rollirrespective of variations in the thickness of the web.

Another object of the invention is to provide means, not dependentsolely on the weight of the roll, for preventing bouncing of the latter.

Still another object of the invention is to provide means for regulatingthe amount of pressure applied through the roll to suit variousoperating conditions and requirements.

The invention contemplates also a means for automatically lifting therider roll from the web when the machine stops, and to lower it when themachine starts.

The invention will be more readily understood by reference to theattached drawings wherein:

Fig. 1 is a fragmentary view in perspective of a typical glue machineillustrating the relative arrangement of rolls and Fig. 2 is a schematicdiagram of the hydraulic system.

With reference to Fig. 1 of the drawings, the numeral 1 indicates theconventional applicator roll of a glue machine, and the numeral 2indicates the doctor or metering roll which is associated inconventional manner with the applicator roll 1. 3 is the rider orpressure roll which functions generally as described above. These threerolls and their relative arrangements are in general conventional, asalso is their operative relation to the paper or other web to which theadhesive is to be applied, such web, indicated by the reference numeral4, travelling between and in contact with the rolls 1 and 3 asillustrated.

In accordance with the present invention, the roll 3 is journalled inarms 5 and 6 at opposite ends respectively of the roll. These arms arepivotally mounted on pins 7 and 8 respectively in the fixed frame (notshown) of the machine. Hydraulic cylinders 9 and 10 are also pivotallymounted, by way of trunnion pins 11 and 12 respectively, in the saidframe, and clevis pins 13 and 14 connect the piston rods 15 and 16 ofthe hydraulic cylinders to the ends of the arms 5 and 6 respectively.

Referring to' the hydraulic circuit illustrated in Fig. 2, a pump17'driven by motor 18 draws oil or other suitable hydraulic medium froma reservoir 19 and supplies it under pressure to pipe line 20. A reliefvalve 21 protects the system from excessive pressure. A metered quantityof oil or other hydraulic medium is supplied to line 22 through apressure compensated orifice 23 of well known commercial form whichresponds to variations in system pressure to maintain a substantiallyconstant volume delivery of the hydraulic medium to the system from thepump. A solenoid valve 24 when deenergized, as illustrated, closes pipeline 25 so that oil flows through line 26 under full pressure to thehead end of cylinders 9 and 10 thereby extending the piston rods 15 and16, rocking the arms 5 and 6 clockwise (as viewed in Fig. 1) on theirrespective pivot pins 7 and 8, and elevating pressure roll 3 out ofengagement with the web 4. The solenoid of valve 24 is preferablyconnected across the circuit of the prime mover of the machine (notshown) so that when the operation of the machine and the travel of theweb 4 is interrupted, the solenoid will be de-energized and the roll 3will be elevated, as described; andwhen the machine is started the roll3 is automatically returned to operative position with respect to the'moving web.

When the machine starts the solenoid valve 24 is energized, asdescribed, so that line 25 is connected to line 27 and therethrough withaccumulator 28, manually adjustable pressure relief valve 29 and gauge30. Under these conditions, the pressure in line 26 and cylinders 9 and10 is reduced to the setting of relief valve 29, which may be adjustedto apply pressure through cylinders 9 and 10m the arms 5 and 6 so as tocounterbalance part of the weight of the roll 3 and to allow it tocontact the paper with desired regulated pressure.

Variations in the thickness of the web and the resultant variations inthe system pressure will be compensated by the cushioning action of theaccumulator 28, the accumulator also affording the degree of resiliencein the system which is necessary to permit the minor adjustments of theroll 3 required for maintenance of a constant pressure relation with thevariable web. Increased thickness in the web tends to reduce systempressure, and decreased thickness tends to increase system pressure. Thevariations are small and the compensation is immediate.

Since the roll 3 may be counterbalanced to any desired degree to preventcrushing, and since the movements of the piston rods 15 and 16 aredampened by flow of the hydraulic medium into and from the accumulator28, bouncing of the roll 3 is inhibited.

As long as the machine remains in operation, the resultant energizationof the solenoid valve 24 will maintain the system in operative conditionwith respect to the pressure function of the roll 3 with the accumulatorand the valve 29 connected in the system with the cylinders 9 and 10. Ifthe operation of the machine is interrupted, the valve 24 will bede-energized and will move automatically into the position shown in thedrawings. The valve 29, and the accumulator will then be disconnectedfrom the pump 17 and full pump pressure will then be applied to the headends of the cylinders 9 and 10 to elevate the roll 3 from the web.

Patented Mar. 10, 1959' I claim:

1. In a mechanism for applying substantially constant pressure within alocalizedfhrea to a surface of a continuously. travellingweb, a.pressure roll. seating against said surface, a.. movable mount for. therollproviding for. displacement of the .roll by the web, and fiuidpressure means. for regulating the. seating pressure of the roll on theweb,,said regulating means comprising afiuid pressure system includingpiston means operatively connected to the roll and actuated bypressurein said system to counterbalance the seating pressureof. theroll on the web, means. fonmaintaininguthe system at a predeterminedsubstantially constant pressure, and means in said system .for absorbingminor variationsin. the pressure in.

said system resultingfrom, displacements of the roll by the web. a

2. Mechanism according to claim 1 including means.

for adjusting the systemlto the desired constant pressure.

3. In a mechanism for applying substantially constant pressure within alocalized area to a. surface of a continuouslytravelling web, a pressureroll seating against said surface, a movablemount for the roll providingfor displacement of the roll by the web, and fluid pressure means forregulating theseating pressure of the. roll on the web, said regulatingmeans comprising a hydraulic system including piston. means operativelyconnected to. the roll mount and actuated by. pressure in the systemtoexert force on the mount counterbalaincing the seating. pressure ofthe roll on the-web, means for adjusting the.

pressure in. said. system and thereby the. said counter balancing force,means for maintaining the systemrsubstantially constant at the adjustedpressure, and pneur matic means in said systenrfor absorbing minorvaria-, tions in the system pressure resulting fromv displacements ofthe roll by the web.

4. In a mechanism forapplying-substantially. constantpressure within alocalized area-to a surface of a continuously'travelling web, a pressurerollseating against said surface, a movable mount for the roll providingfor displacement of the roll by the web, hydraulic piston meansconnected with the mount incounterbalancing relation with the roll'andconstituting a means for regulating the pressure of the roll on the web,'a' constant volume hydraulic pressure source connected to the pistonmeans for actuating the latter to counterbalance the roll, pressurerelief means'conne'cted to the piston means for limiting the hydraulicpressure applied to the latter, and means for adjusting'said reliefmeans to regulate the pressure of the roll on the web.

5. Mechanism according to claim 4 including pneumatic means connected tothepiston means for absorbing minor variations in the hydraulic pressureimposed upon i the relief means by displacements of the rolls by theweb.

6. In a mechanism for applying substantially constant pressure within alocalized area to a surface of a continuously travelling web, a pressureroll seating against said surface, a movable mountfor the roll providingfor displacement of the roll by the web, hydraulic piston meansconnected with the mount in counterbalancing relation with the roll andconstituting a means for regulating the pressure of the roll on the web,a constant volume hydraulic pressure source, a pipe line forming adirect connection between the source and the piston means, a reliefvalve for limiting the hydraulic pressure on the pistonmeans and meansfor adjusting the valve to regulate said pressure, an accumulator forabsorbing minor pressure fluctuations in the line resulting fromdisplacement of the roll by the Web, and a valve for selectivelyconnecting and disconnecting the said accumulator and relief valve tothe pipe line.

7. In a mechanism for applying" adhesive to the tips of the corrugationsat one face of a continuously travelling corrugated web, an adhesiveapplicator roll at said face, a pressure roll exerting pressure on theopposite face of the web to press'thc said'tips against the applicatorroll, a movable mount for the pressure roll' providingfor displacementof the roll by irregularities in the web,

hydraulic piston means connected to the pressure roll mount incounterbalancing relation to the roll and constituting a means forregulating the pressure of the roll on the web, a constant volumehydraulic presure source and a line connecting the source to the pistonmeans for actuating the latter to counterbalance the roll, means forregulating the pressure applied to the piston means from said source,and means for absorbing minor pressure" fluctuations in said lineresulting from displacement of the roll by the web.

8. Mechanism according to claim 7 'v'vher'ein the means for regulatingthe pressure applied to the piston means comprises an adjustable reliefvalve connected to said line, and wherein further valve means isprovided for selectively breaking and making said connection.

9. Mechanism according to claim 7 wherein the means for absorbingpressure fluctuation in the line consistsof a pressure accumulatorconnected between the said pressure source and the piston means.

References Cited in the tile of this patent- UNITED STATES PATENTS2,365,621 Bender Dec. 19, 1944 2,366,210 Murch et al. Ian. 2, 19452,575,590 Goulding Nov. 20, 1951 2,691,326 McArn Oct. 12, 1954

